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1.
Females of the medfly, Ceratitis capitata, prefer sucrose solutions containing ribonucleotides to sucrose solutions without them. The order of preference for the nucleotides was: 5GMP>GTP>5CMP>5IMP >dGMP>5UMP>5AMP>5XMP=ATP=2 & 3GMP=RP>3AMP.2AMP, guanosine, inosine, adenine and 5TMP produced no significant stimulation. Females sterilized by irradiation showed reduced attraction to 5GMP as compared to non-irradiated females.Optimal molecular configuration for phagostimulation includes: phosphorylation at the 5 position of the ribose, free hydroxyl groups at 2 and 3 on the ribose, and an NH2 group at the 2 position of the aromatic ring of purine.It is proposed that the 5GMP in yeast hydrolyzate can be used as a measure of the suitability of the hydrolyzate as a bait.
Résumé La femelle de la mouche méditerranéenne des fruits, Ceratitis capitata, préfère les solutions de sucrose contenant des ribonucléotides aux simples solutions de sucrose. Lórdre de préférence pour les nucléotides est le suivant: 5GMP>GTP>5CMP>5IMP >dGMP>5UMP>5AMP>5XMP=ATP =2 & 3GMP=RP>3AMP.Le 2AMP, la guanosine, l'inosine, l'adénine et le 5TMP provoquent une stimulation significative. Les femelles montrent aprés stérilisation par irradiation une attirance réduite pour le 5GMP par comparaison avec les femelles non-irradiées.La configuration moléculaire optimale pour la phagostimulation comprend: la phosphorylation en position 5 du ribose; des groupes hydroxyles libres en 2 et 3 sur le ribose; et un groupe NH2 en position 2 sur le noyau aromatique.Nous proposons que le 5GMP dans l'hydrolysat de levure puisse être utilisé pour mesurer la capacité de l'hydrolysat comme appât.

Abbreviations 5AMP Adenosine 5-monophosphate - 3AMP Adenosine 3-monophosphate - 2AMP Adenosine 2-monophosphate - dAMP 2-deoxyadenosine 5-monophosphate - ADP Adenosine 5-diphosphate - ATP Adenosine 5-triphosphate - 5GMP Guanosine 5-monophosphate - 2GMP Guanosine 2-monophosphate - 3GMP Guanosine 3-monophosphate - dGMP 2-deoxyguanosine 5-monophosphate - GDP Guanosine 5-diphosphate - GTP Guanosine 5-triphosphate - 5IMP Inosine 5-monophosphate - IDP Inosine 5-diphosphate - ITP Inosine 5-triphosphate - 5XMP Xanthosine 5-monophosphate - 5CMP Cytidine 5-monophosphate - dCMP 2 deoxycytidine 5-monophosphate - CTP Cytidine 5-triphosphate - 5UMP Uridine 5-monophosphate - 5TMP Thymidine 5-monophosphate - RP Ribose 5 monophosphate  相似文献   

2.
Upon exposure of the middle phalanx of the finger to air at -10° to-15°C moving at 10 m/sec, the surface temperature cooled not toward air temperature but toward a higher temperature, T = (Ta + ). This was due to heat input, about 118 joule over 4.3 min, by conduction from the proximal and distal phalanges not exposed to the cold air. Calculated thermal constants for the finger are somewhat different from those for water and account for the rapidity of the cooling. The incidence of either freezing or cold-induced vasodilatation could not be correlated with the relative cooling rate because of the occurrence of indeterminate supercooling. Within the same range of supercooled temperatures, freezing occurred in 16 cases, cold induced vasodilatation in 7 cases, and nothing in 3 cases. The factors which induce crystallization on the one hand or vasodilatation on the other hand, remain to be discovered.
Zusammenfassung Wenn das Mittelglied eines Fingers einer Temperatur von -10° bis -15°C bei einem Wind von 10 m/sec ausgesetzt wurde, kühlte die Hauttemperatur nicht bis zur Lufttemperatur, sondern bis zu einer höheren Temperatur T = (Ta + ) ab. Dies war Folge des Wärmezuflusses, etwa 118 joule über 4.3 min, durch Konduktion von den nicht exponierten proximalen und distalen Fingergliedern. Die berechneten Wärmekonstanten für den Finger waren verschieden von denen für Wasser und erklären die Schnelligkeit der Abkühlung. Die Häufigkeit von Erfrieren oder kältebedingter Gefässerweiterung liess sich wegen des Auftretens unbestimmter Ueberkühlung nicht mit der relativen Abkühlungsrate korrelieren. Innerhalb des gleichen Bereiches überkühlter Temperaturen traten in 16 Fällen Erfrierungen, in 7 Fällen kältebedingte Gefässerweiterung und in 3 Fällen nichts auf. Die Faktoren die entweder Kristallisation oder Gefässerweiterung bedingten, sind unbekannt.

Resume Lorsque l'on expose la deuxième phalange à une température de -10° à -15°C par un vent de 10 m/sec, sa température de surface ne s'abaisse pas jusqu'à celle de l'air ambiant, mais seulement jusqu'à une valeur T = (Ta + ). Ceci est dû à l'échange de chaleur — environ 118 joules pour 4,3 min — provenant de la troisième et de la première phalange non exposées à l'air froid. Les constantes thermiques calculées sont différentes de celles de l'eau, ce qui explique le refroidissement rapide du corps humain. Les causes de gelure ou de vasodilatation due au froid ne peuvent pas être mises en corrélation avec le taux de refroidissement relatif en raison de l'apparition inexpliquée de phénomènes de surrefroidissement. Dans le même intervalle de températures basses, on a constaté 16 cas de gelures, 7 de vasodilatation due au froid et, dans 3 cas, aucune modification n'est apparue. Les faits qui provoquent soit la cristallisation, soit la vasodilatation ne sont pas connus jusqu'ici.
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3.
Diiminosuccinonitrile (DISN), formed by the oxidation of diaminomaleonitrile (DAMN), has been investigated as a potential prebiotic phosphorylating agent. DISN effects the cyclization of 3-adenosine monophosphate to adenosine 2, 3-cyclic phosphate in up to 39% yield. The mechanism of this reaction was investigated. The DISN-mediated phosphorylation of uridine to uridine monophosphate does not proceed efficiently in aqueous solution. The reaction of DISN with uridine-5-phosphate and uridine results in the formation of 2,2-anhydronucleotides and 2,2-anhydronucleosides respectively, and other reaction products resulting from an initial reaction at the 2- and 3-hydroxyl groups. The clay mineral catalysis of the cyclization of adenosine-3-phosphate was investigated using homoionic montmorillonites.  相似文献   

4.
Until recently, the endangered Humboldt penguin was considered a sedentary bird, which remained near its breeding colonies throughout the year. In this pilot study we used five satellite transmitters on Humboldt penguins during the austral winter and were able to track one bird from Pan de Azúcar Island (26°09S, 70°40W), Northern Chile to Iquique (20°12S, 70°07W), a distance of 640 km, between May 24 and June 26, 1996. While a 35 km protection zone around breeding islands might be helpful to prevent competition of penguins with fisheries during the summer months, this might not improve the survival of migrating birds in the winter. Further studies are required to determine the extent of migration and to confirm the recorded travelling route and landing locations in order to detect possible threats to Humboldt penguins from fishing and other industries throughout the year.
Zusammenfassung Während noch vor wenigen Jahrzehnten Millionen Humboldtpinguine die Küsten Perus und Chiles bevölkerten, wird die Art heute als gefährdet eingestuft. Die Fischerei stellt die größte Bedrohung für diese Tierart dar, deren Gesamtbestand sich nach letzten Schätzungen nur noch auf 10 000 Individuen beläuft. Wir setzten im Südherbst 1996 fünf Argos-Satellitensender ein, um festzustellen, ob Humboldtpinguine des Naturschutzgebietes Pan de Azúcar (26°09S) im Winter ortstreu bleiben oder saisonale Wanderungen durchführen. Während sich vier der Vögel im Untersuchungszeitraum (18–74 Tage) nicht weiter als 87 km von ihrer Brutinsel entfernten, wanderte ein Vogel im Juni 1996 nach Norden bis vor die Stadt Iquique (20° 12S, 640 km vom Ausgangspunkt entfernt). Obwohl die in einer früheren Studie ermittelte Größe eines marinen Schutzgebietes von 35 km Durchmesser rund um die Brutinsel in den Sommermonaten ausreichend sein mag, belegen die neuen Ergebnisse, daß weitere Untersuchungen über das Wanderverhalten der Humboldtpinguine als Grundlage für einen effektiven Artenschutz unerläßlich sind.
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5.
Summary The syntheses of 4,4-biphenyl tetrazonium chloride monohydrate, of 1,1-di-(3-nitrophenyl)-3,3-dimethyl-5,5-(4,4-biphenylene)-diformazan, and of yellow tetrazolium [2,2-di-(3-nitrophenyl)-5,5-dimethyl-3,3-(4,4-biphenylene)-ditetrazolium chloride] are described. Solutions of the pure formazan in pyridine absorb visible light maximally at 455 nm; 455 is 54,050. Yellow tetrazolium has been specifically designed to meet the requirement of a new technique in quantitative cytochemistry, which involves the consecutive use of two bistetrazolium salts on the same tissue section.I thank Professor L. Young of St. Thomas's Hospital Medical School and Professor C. Long of the Royal College of Surgeons for their interest and encouragement. I am greatly indebted to a large number of friends and colleagues for helpful discussion, and to Dr. A. Deavin and Miss A. Banks for exploratory experiments which involved column chromatography. Microanalyses were carried out by Mr. G. S. Crouch at the London School of Pharmacy.  相似文献   

6.
Zusammenfassung Mäusen mit einem transplantierbarem Melanom, Typ Harding-Passey, wurde H-3-markiertes Dl-DOPA-, -T2, Dl-DOPA-2,5,6-T3, Dl-Prolin-2-T und L-Ty-rosin-3-T' injiziert und die H-3-Inkorporation in verschiedenen Zellarten des Melanom autoradiographisch zu verschiedenen Zeiten untersucht.H-3-DOPA wird selektiv in Melanin eingebaut. Dieses H-3-Melanin findet sich 1,5–24 Std nach Gabe des H-3-DOPA in Bindung an feine Melaningranula im Cytoplasma melaninarmer Melanocyten. Macrophagen dagegen enthalten zu dieser Zeit kaum H-3-Melanin. Nach 5 Tagen aber ist das H-3-Melanin fast ausschließlich in den Macrophagen nachzuweisen. Die Menge des synthetisierten H-3-Melanin war unabhängig davon, ob DOPA-, -T2 oder DOPA-2,5,6-T3 als H-3-Melaninvorstufe diente.Der Eiweißstoffwechsel wurde mit H-3-Prolin und H-3-Tyrosin untersucht. Die Eiweißneubildung in Melanoblasten und jugendlichen Melanocyten lag in der gleichen Größenordnung wie die der Leberparenchymzellen, während sie in Melaninspeicherzellen etwa zehnmal geringer war. Wurden die Versuchstiere erst 7 Tage nach Injektion der H-3-Aminosäure getötet, so war das H-3-Eiweiß aller Zellen zu 70–90% bereits wieder abgebaut, nur bei den Macrophagen stieg der Gehalt an H-3-Eiweiß auf das Doppelte an. Dies wird durch Phagocytose H-3-markierter Eiweiß-Melanin-Granula erklärt.Die H-3-Markierung des Tyrosin-3-T wurde nur zu einem autoradiographisch im Vergleich zur H-3-Markierung des Eiweißes nicht mehr faßbaren Bruchteil in Melanin eingebaut.Die Arbeit wurde durch Mittel der Deutschen Forschungsgemeinschaft und des Bundesministeriums für Atomkernenergie unterstützt.  相似文献   

7.
The production of 5-IMP and 5-GMP by enzymatic conversion from RNA using a continuous two packed-bed reactor was investigated. 5-Phosphodiesterase (5PD) and 5-adenylate deaminase (5AD) were immobilized in an acrylic resin to produce derivatives with about 15 U/g of support. The kinetic properties of the enzymes were described by Michaelis-Menten models: no significant differences were found in the K m value of the free and immobilized 5AD (60 and 20 m, respectively), whereas for 5PD the K m value was one order of magnitude higher for the immobilized enzyme (4.85 mg RNA/ml), probably due to diffusional limitations. Both enzymes remained stable after 8 h of use in a continuous packed-bed reactor whereas the half lives of the free enzymes were 193 min and 240 min at 40°C and 70°C for 5AD and 5PD, respectively. A procedure is proposed for the design of a continuous two packed-bed column process.F. Olmedo and F. Iturbe are with the Depto. de Alimentos y Biotecnologia, Facultad de Química, UNAM, México 04510, D.F., Mexico. J. Gomez-Hernández is with the Depto. de Biotecnología, UAM-1, Apdo. Postal 55-535, México 09340, D.F., Mexico. A. López-Munguía is with the Instituto de Biotecnología, Apartado Postal 510-3, Cuernavaca, Mor. 62271, Mexico  相似文献   

8.
Zusammenfassung Die Adenosindesaminasen der Primaten zeigen eine genetisch determinierte Variabilität. Bei der Untersuchung von 327 subhumanen Primaten (289 Simiae der Alten Welt, 38 Prosimiae) konnten wir neun Adenosindesaminase-Varianten nachweisen, die auf Grund ihrer unterschiedlichen elektrophoretischen Wandergeschwindigkeit als ADA 6, ADA 4, ADA 2, ADA 2, ADA 1, ADA 3, ADA 5, ADA 5 und ADA 7 bezeichnet werden. Die Verteilung der verschiedenen Phänotypen wurde ermittelt.
Red cell enzymes of primatesAdenosine deamisnase (EC: 3.5.4.4.)
Summary The polymorphism of adenosine deaminase has been investigated in 327 subhuman Primates (289 Old World Monkeys and 38 Prosimians). Nine adenosine deaminase variants were found to be present, which on the basis of their different electrophoretic mobilities were designated ADA 6, ADA 4, ADA 2, ADA 2, ADA 1, ADA 3, ADA 5, ADA 5 and ADA 7. The distribution of these various phenotypes has been estimated.


Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.  相似文献   

9.
Zusammenfassung In den vorliegenden Untersuchungen wird die anisotrope 1:9-Dimethyl-Methylenblau- bzw. N,N-Diäthylpseudoisocyaninchloridfärbung an der Erythrocytenmenbran studiert und mit der topooptischen Toluidinblaufärbung verglichen.Die Abweichung zwischen anisotroper Toluidinblau- und 1:9-Dimethyl-Methylenblaufärbung sind (außer nach KMnO4-Oxydation) nur quantitativer Natur. Demgegenüber sind die Unterschiede der N,N-Diäthylpseudoisocyaninchloridfärbung zur Toluidinblau- und zu den 1:9-Dimethyl-Methyllenblaufärbungen nach enzymatischen und chemischen Abbaureaktionen beträchtlich, denn nach den Vorbehandlungen ist die N,N-Diäthylpseudoisocyaninchloridfärbung praktisch ausgelöscht.Die Membrandoppelbrechung nach diesen Behandlungen ist durch eine anschließende Aldehyd-Bisulfitbildung oder KMnO4-Oxydation mit 1:9-Dimethyl-Methylenblaufärbung vollkommen restaurierbar, die N,N-Diäthylpseudoisocyaninchloridfärbung ist es nur nach einer anschließenden KMnO4-Oxydation.Nach Methylierung bzw. Acetylierung ist die Membrandoppelbrechung aufgehoben, jedoch nach KMnO4-Oxydation mit beiden topo-optischen Färbungen wieder vorhanden. Nach der Digitonin-Behandlung haben wir eine Umorientierung der Glykokalyxkomponenten gesehen.Die Befunde weisen auf die Bedeutung der räumlichen Orientierung der Membranglykoproteine an Erythrocyten hin. Die durchgeführten histochemischen Vorbehandlungen demonstrieren die Rolle der Glykokalyx für die drei topo-optische Reaktionen.
Investigation on the anisotropy of glycocalyx stained with 1.9-dimethyl methylene blue and N,N-diethylpseudoisocyanine chloride
Summary In the present study the anisotropic staining of the erythrocyte membrane with 1.9-dimethyl methylene blue and N,N-diethylpseudoisocyanine chloride was studied and simultaneously compared with the toluidine blue topo-optical staining. The difference between anisotropic toluidine blue and 1.9-dimethyl methylene blue staining, except after KMnO4-oxidation, was only of quantitative nature. On the contrary, striking differences were observed between N,N-diethylpseudoisocyanine chloride staining, and toluidine blue or 1.9-dimethyl methylene blue staining. Enzymatic and chemical degradation resulted the disappearance of N,N-diethylpseudoisocyanine chloride staining.Following these treatment membrane birefringence could be restored by aldehyde bisulfate and/or KMnO4-oxidation, while the N,N-diethylpseudoisocyanine chloride staining was restored only after KMnO4-oxidation.After methylation or acetylation the membrane birefringence disappears, while after KMnO4-oxidation both topo-optical reactions return. The digitonin reaction brought about a rearrangement of the glycocyalyx components. The results draw attention to the spatial orientation of the glycoprotein of the erythrocyte membrane. The role of glycocalyx in the three topo-optical reactions was thus clearly demonstrated.
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10.
Summary The effect of the glycosidic torsion angle on 13C and 15N shifts of the sugar and base moieties of guanosine nucleotides was investigated by comparing the sites in two model G-tetrad oligodeoxynucleotides that contain guanosine residues alternately with syn and anti bases. The sugar puckering has been shown to be C2-endo for both cases. It was observed that, for the instances with syn bases, the C1 through C4 carbons showed shifts that may be distinguished from those normally found in B-DNA-like structures. C1, C3 and C4 moved to lower field, while C2 moved to higher field. Effects of the change in glycosidic torsion angle were also seen in the shifts of base carbons and nitrogens in the five-membered ring portion of the base. Characterization of the shift variation associated with this conformational change may be useful in developing the use of 13C shifts as a tool in conformational analysis of oligonucleotides.Part of the work reported here derives from the Ph.D. Thesis of Karen L. Greene, Emory University, Atlanta, GA, 1991.  相似文献   

11.
The six binary montmorillonite clay-catalyzed reactions of the5-phosphorimidazolides of adenosine, cytidine, guanosine anduridine were performed and the eight dimers from each reactionwere separated and analyzed by HPLC. A 16–51-fold higher yieldof the 5-purine-pyrimidine dimers over that of the5-pyrimidine-purines was observed. The total yield of the5-purine-pyrimidine dimers was in the 50–70% range while thatof the 5-pyrimidine-purine dimers was 1.3–7.0%. Less sequenceselectivity was observed in the homodimers formed.Regioselectivity for the formation of 3, 5-phosphodiesterbonds over that found in the absence of clay was observed. The5-purine-pyrimidine, 5-pyrimidine-pyrimidine and5-purine-purine dimers had 3, 5-links in about half of theirphosphodiester bonds. The percent phosphodiester links in the5-pyrimidine-pyrimidine dimers was 18%, a value close to thatobserved in the absence of the montmorillonite catalyst. Themontmorillonite-catalyzed reaction of all four activatednucleotides was performed and the 24 products were separated andanalyzed. The trends observed in the binary reactions wereconfirmed and the results also showed that the relativereactivity of the activated monomers was A>G>C>U in theratio 8.2: 4.8: 1.3: 1 respectively. No 5-pyrimidine-purineswith a 5-U and pG3pU, pC3pAand pC3pG weredetected. These studies suggest that a limited population ofRNAs would have formed in catalyzed prebiotic reactions.  相似文献   

12.
Zusammenfassung Aus fünf antarktischen Bodenproben von 60°45, 62°14 und 63°24 südlicher Breite wurden in 92 Ansätzen drei niedere Phycomyceten herausgeködert, nämlich Rhizophydium utriculare, Rhizophydium sphaerotheca und Hyphochytrium cf. catenoides. Sie alle sind auch von Standorten mit milderem Klima bekannt und Kosmopoliten.  相似文献   

13.
R. Wiermann 《Planta》1971,102(1):55-60
Summary Chalcone-flavanone isomerase from the anthers of Lilium candidum and Tulipa cv. Apeldoorn exhibits a distinct substrate specificity. The enzyme catalyses only the isomerization of 2,4,4,6-tetrahydroxychalcone, whereas it is not active with 2,4,4-trihydroxychalcone.During the final stage in the development of the anthers, differing isomerase activities were observed. Maximum enzyme activity was measured at a point when the concentration of chalcones was decreasing rapidly and the concentration of flavonols was increasing. These findings strongly support the suggestion that the isomerase plays an important role in flavonoid metabolism.

Untersuchungen zum Phenylpropanstoffwechsel des Pollens VI.  相似文献   

14.
Summary (3H)DIDS (4,4-diisothiocyano-2,2-ditritiostilbene-disulfonate) was used as a convalent label for membrane sites involved in anion permeability. The label binds to a small, superficially located population of sites, about 300,000 per cell, resulting in almost complete inhibition of anion exchange. The relationship of biding to inhibition is linear suggesting that binding renders each site nonfunctional. In the inhibitory range less than 1% of the label is associated with lipids but at higher concentrations of DIDS, the fraction may be as high as 4%. In ghosts, however, treatment with (3H)DIDS results in extensive labeling of lipids. In cells, a protein fraction that behavens on SDS acrylamide gels as thought its molecular weight is 95,000 daltons (95K) is predominatly labeled by (3H)DIDS. The only other labeled protein is the major sialoglycoprotein which contains less than, 5% of the total bound (3H)DIDS. Because of the linear relationship of binding to inhibition and the unique architecture of the site, it is suggested that the (3H)DIDS-binding site of the 95K protein is the substrate binding site of the anion transport system. The 95K protein is asymmetrically arranged in the membrane with the sites arranged on the outer face accessible to agent in the medium. In leaky ghost, only a few additional binding sites can be reached from the inside of the membrane in the 95K protein, in contrast to the extensive labeling of other membrane proteins in ghosts as compared to cells.Abbreviations DADS 4,4-Diamino-2,2-dihydrostilbene disulfonic acid - DIDS 4,4-Diisothiocyano-2,2-stilbene disulfonic acid - (3H)DADS 4,4-Diamino-2,2-ditritiostilbene disulfonic acid - (3H)DIDS 4,4-Diisothiocyano-2,2-ditritiostilbene disulfonic acid  相似文献   

15.
The extrathyroidal conversion of thyroxine to triiodothyronine in the snake, Elaphe taeniura, has been determined in vitro. The liver, kidney and pancreas are important organs showing significant 5-deiodinase activity. The pancreas has a higher conversion rate (18.5±3.58 pmol·min-1·mg protein-1) than other vertebrate tissues that have been studied. The 5-deiodinase activity is dependent on substrate (thyroxine) concentration, cofactor, i.e. dithioerythritol concentration, temperature, duration of incubation and pH. It is sensitive to iopanoic acid, propylthiouracil, salicylate and propranolol. It is also indicative that the 5-deiodinase activity increased and decreased, respectively, in snakes with experimentally induced hyper- and hypo-thyroidism. These characteristics suggest that snake 5-deiodinase is similar to that of mammals, probably of type I category.Abbreviations ANOVA analysis of variance - BSA bovine serum albumin - BW body weight - cpm counts per minute - 5D 5-deiodinase - DTE dithioerythritol - EDTA ethylenediamine tetraacetate - IOP iopanoic acid - K m Michaelis-Menten constant - L/D Light/Dark - MW molecular weight - NRS normal rabbit serum - PEG polyethylene glycol - %B percentage of added label found in the pellet - PTU propylthiouracil - RIA radioimmunoassay - rT3 3,5,5-triiodothyronine - SPSS Statistical Package for the Social Sciences - T3 3,5,3-triiodothyronine - T4 thyroxine - TRIS Tris (hydroxymethyl) aminomethane - Tx thyroidectomized - V max maximum velocity of enzyme reaction  相似文献   

16.
Summary 2-Amino-2-deoxyuridine reacts efficiently with nucleoside 5-phosphorimidazolides in aqueous solution. The dinucleoside monophosphate analogues were obtained in yields exceeding 80% under conditions in which little reaction occurs with the natural nucleosides.In a similar way, the 5-phosphorimidazolide of 2-amino-2-deoxyuridine undergoes self-condensation in aqueous solution to give a complex mixture of oligomers.The phosphoramidate bond in the dinucleoside monophosphate analogues is stable for several days at room temperature and pH 7. The mechanisms of their hydrolysis under acidic and alkaline conditions are described.Abbreviations A adenosine - C cytidine - G guanosine - U uridine - T thymidine - UN 3 2-azido-2-deoxyuridine - UNH 2 2-amino-2-deoxyuridine - ImpA adenosine 5-phosphorimidazolide - ImpU uridine 5-phosphorimidazolide - ImpUN 3 2-azido-2-deoxyuridine 5-phosphorimidazolide - ImpUNH 2 2-amino-2-deoxyuridine 5-phosphorimidazolide - pA adenosine 5-phosphate - pU uridine 5-phosphate - pUN 3 2-azido-2-deoxyuridine 5-phosphate - pUNH 2 2-amino-2-deoxyuridine 5-phosphate - UpA uridylyl-[35]-adenosine - UpU uridylyl-[35]-uridine - UNpA adenylyl-[52]-2-amino-2-deoxy-uridine - UNpU uridylyl-[52]-2-amino-2-deoxyuridine (pUN)n n=2,3,4 [25]-linked oligomers of pUNH 2 poly(A) polyadenylic acid - Im imidazole - MeIm l-methylimidazole  相似文献   

17.
Crude extracts or supernatants of broken cells of Clostridium formicoaceticum reduce unbranched, branched, saturated and unsaturated carboxylates at the expense of carbon monoxide to the corresponding alcohols. The presence of viologens with redox potentials varying from E 0=-295 to-650 mV decreased the rate of propionate reduction. The more the propionate reduction was diminished the more formate was formed from carbon monoxide. The lowest propionate reduction and highest formate formation was observed with methylviologen. The carbon-carbon double bond of E-2-methyl-butenoate was only hydrogenated when a viologen was present. Formate as electron donor led only in the presence of viologens to the formation of propanol from propionate. The reduction of propionate at the expense of a reduced viologen can be followed in cuvettes. With respect to propionate Michaelis Menten behavior was observed. Experiments are described which lead to the assumption that the carboxylates are reduced in a non-activated form. That would be new type of biological reduction.Non-standard abbreviations glc Gas liquid chromatography - HPLC high performance liquid chromatography - RP reverse phase; Mediators (the figures in parenthesis of the mediators are redox potentials E 0 in mV) - CAV2+ carbamoylmethylviologen, 1,1-carbamoyl-4,4-dipyridinium dication (E 0=-296 mV) - BV2+ benzylviologen, 1,1-dibenzyl-4,4-dipyridinium dication (E 0=-360 mV) - MV methylviologen, 1,1-dimethyl-4,4-dipyridinium-dication (E 0=-444 mV) - DMDQ2+ dimethyldiquat, 4,4-dimethyl-2,2-dipyridino-1,1-ethylendication (E 0=-514 mV) - TMV2+ tetramethylviologen, 1,1,4,4-tetramethyl-4,4-dipyridinium dication (E 0=-550 mV) - PDQ2+ propyldiquat, 2,2-dipyridino-1,1-propenyl dication (E 0=-550 mV) - DMPDQ2+ dimethylpropyldiquat, 4,4-dimethyl-2,2-dipyridino-1,1-propenyl dication (E 0=-656 mV) - PN productivity number=mmol product (obtained by the uptake of one pair of electrons) x (biocatalyst (dry weight) kg)-1×h-1  相似文献   

18.
Summary In the human proteolipid protein gene, the base sequence of the intronic region 5 to exon 6 was found to be 5-ctctttcattttcctgcag-3 and not 5-ctctttt-cattttcctgcag-3 as previously reported.  相似文献   

19.
Summary Adenosine 5-phosphoramidates form when solutions containing adenosine 5-polyphosphates pnA (n 3) or P1, P2-diadenosine 5-diphosphate and amines are allowed to dry out. Mg ions catalyze these reactions. We have studied systems containing ammonia, imidazole, glycine, ethylenediamine and histamine. The yields of adenosine 5-phosphoramidates range from 10–50 % based on the nucleotide. The prebiotic significance of the reactions is discussed.Abbreviations Im imidazole - hist histamine - gly glycine - en ethylenediamine - CDI 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride - EDTA ethylenediaminetetraacetic acid - A adenosine - Pn (n = 1, 2 ) linear polyphosphate containing n phosphate residues - pnA adenosine 5-polyphosphate containing n phosphate residues - ADP adenosine 5-diphosphate - ATP adenosine 5-triphosphate - AppA P1, P2-diadenosine 5-diphosphate - gly-pA adenylyl-(5N)-glycine - ImpA adenosine 5-phosphorimidazolide - NH2-pA adenosine 5-phosphoramidate - en-pA adenylyl-(5N)-ethylenediamine - hist (NH) - pA adenosine 5-phospho-[2-(4-imidazolyl)-ethylamide] - hist(Im)-pA adenosine 5-phospho-[4-(2-aminoethyl)-imidazolide] - enP1,2 phosphoramidates of ethylenediamine derived from H3PO4 and H4P2O7  相似文献   

20.
Summary The left part of the SPP1 chromosome can be defined by the presence of dispensable DNA. With this definition, the polarities of the separable H and L strands of SPP1 DNA are 5–3 and 3–5, respectively, from left to right.Part of this work was taken from the doctoral thesis of M.A.M., which is to be submitted to the Freie Universität, Berlin  相似文献   

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